Abstract: Objective  To explore the identification of baseline unconjugated bilirubin(UBiL)  cutoffs for whether the early lifestyle weight loss is up to standard in obese people. Methods  314 simple obese people who underwent weight management  were included for weight loss by recording the weight of baseline and after 3 months. The percentage of weight loss greater than 10% was defined as successful weight loss, which was divided into standard group and  nonstandard group. Binary logistic regression analysis were used to study the influencing factors for whether the weight  loss was up to standard. The sensitivity and specificity of baseline unconjugated bilirubin were evaluated for predicting weight loss by using receiver operating characteristic curve. Results  UBiL was the influencing factor of weight loss among women. ROC curve analysis showed that the area under the ROC curve of UBiL in women was 0.747(95%CI 0.622, 0.871), cutoff value was 9.50  μmol/L, and  Yoden index was 0.416. Sensitivity and specificity were  52.4% and  89.2%,  respectively. Conclusion  Baseline unconjugated bilirubin has a high specificity for predicting whether women's lifestyle weight loss is up to standard. We recommend adding drugs, weight loss surgery and other weight loss methods as soon as possible based on lifestyle weight loss，when the baseline unconjugated bilirubin is less than 9.50  μmol/L.

Key words: unconjugated bilirubin, obesity, lifestyle